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        <h2>
          <span class="refentrytitle">seed</span>
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        <p>seed — 
      Sets the global seed value.
          </p>
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      <div class="refsect1">
        <a id="idp144813232"></a>
        <h2>Description</h2>
        <p>
      Sets the global seed value for all <span class="emphasis"><em>x-class noise generators</em></span>, as well as other opcodes that use a random call, such as <a class="link" href="grain.html" title="grain"><em class="citetitle">grain</em></a>.
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        <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
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              <th align="left">Please Note</th>
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                <p><a class="link" href="rand.html" title="rand"><em class="citetitle">rand</em></a>, <a class="link" href="randh.html" title="randh"><em class="citetitle">randh</em></a>, <a class="link" href="randi.html" title="randi"><em class="citetitle">randi</em></a>, <a class="link" href="rnd.html" title="rnd"><em class="citetitle">rnd(x)</em></a> and <a class="link" href="birnd.html" title="birnd"><em class="citetitle">birnd(x)</em></a> are not affected by seed.</p>
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      <div class="refsect1">
        <a id="idp144821472"></a>
        <h2>Syntax</h2>
        <pre class="synopsis"><span class="command"><strong>seed</strong></span> ival</pre>
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      <div class="refsect1">
        <a id="idp144823520"></a>
        <h2>Performance</h2>
        <p>
      Use of <span class="emphasis"><em>seed</em></span> will provide predictable results from an orchestra using with random generators, when required from multiple performances.
    </p>
        <p>
      When specifying a seed value, <span class="emphasis"><em>ival</em></span> should be an integer between 0 and 2<sup>32</sup>. If <span class="emphasis"><em>ival</em></span> = 0, the value of <span class="emphasis"><em>ival</em></span> will be derived from the system clock.
    </p>
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      <div class="refsect1">
        <a id="idp144827632"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the seed opcode. It uses the file <a class="ulink" href="examples/seed.csd" target="_top"><em class="citetitle">seed.csd</em></a>.
      </p>
        <div class="example">
          <a id="idp144829488"></a>
          <p class="title">
            <strong>Example 790. Example of the seed opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac     <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if RT audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o seed.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">nchnls</span> <span class="op">=</span> 2
<span class="ohdr">0dbfs</span>  <span class="op">=</span> 1

<span class="oblock">instr</span> 1	<span class="comment">;same values every time</span>

<span class="ohdr">seed</span> 10
krnd <span class="opc">randomh</span> 100, 200, 5
     <span class="opc">printk</span> .5, krnd			<span class="comment">; look </span>
aout <span class="opc">oscili</span> 0.8, 440<span class="op">+</span>krnd, 1		<span class="comment">; &amp; listen</span>
     <span class="opc">outs</span> aout, aout

<span class="oblock">endin</span>

<span class="oblock">instr</span> 2	<span class="comment">;different values every time - value is derived from system clock</span>

<span class="ohdr">seed</span> 0					<span class="comment">; seed from system clock</span>
krnd <span class="opc">randomh</span> 100, 200, 5		
     <span class="opc">printk</span> .5, krnd			<span class="comment">; look </span>
aout <span class="opc">oscili</span> 0.8, 440<span class="op">+</span>krnd, 1		<span class="comment">; &amp; listen</span>
     <span class="opc">outs</span> aout, aout

<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="stamnt">f</span> 1 0 16384 10 1	<span class="comment">;sine wave.</span>

<span class="stamnt">i</span> 1 0 1
<span class="stamnt">i</span> 2 2 1
<span class="stamnt">e</span>
<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
        </div>
        <p><br class="example-break" />
      Its output should include lines like:
      </p>
        <pre class="screen">
i   1 time     0.00067:   100.00000
i   1 time     0.50000:   175.78677
i   1 time     1.00000:   170.89579

WARNING: Seeding from current time 834128659

 i   2 time     2.00067:   100.00000
 i   2 time     2.50000:   197.58517
 i   2 time     3.00000:   188.69525
      </pre>
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